• Genome-wide association meta-analyses combining multiple risk phenotypes provide insights into the genetic architecture of cutaneous melanoma susceptibility

      Landi, MT; Bishop, D T; MacGregor, S; Machiela, MJ; Stratigos, AJ; Ghiorzo, P; Brossard, M; Calista, D; Choi, J.; Fargnoli, MC; et al. (2020)
      Most genetic susceptibility to cutaneous melanoma remains to be discovered. Meta-analysis genome-wide association study (GWAS) of 36,760 cases of melanoma (67% newly genotyped) and 375,188 controls identified 54 significant (P < 5 x 10(-8)) loci with 68 independent single nucleotide polymorphisms. Analysis of risk estimates across geographical regions and host factors suggests the acral melanoma subtype is uniquely unrelated to pigmentation. Combining this meta-analysis with GWAS of nevus count and hair color, and transcriptome association approaches, uncovered 31 potential secondary loci for a total of 85 cutaneous melanoma susceptibility loci. These findings provide insights into cutaneous melanoma genetic architecture, reinforcing the importance of nevogenesis, pigmentation and telomere maintenance, together with identifying potential new pathways for cutaneous melanoma pathogenesis.
    • Pan-cancer analysis of whole genomes

      Campbell, P. J.; Getz, G.; Korbel, J. O.; Stuart, J. M.; Jennings, J. L.; Stein, L. D.; Perry, M. D.; Nahal-Bose, H. K.; Ouellette, B. F. F.; Li, C. H.; et al. (2020)
      Fibrosis and fat replacement in skeletal muscle are major complications that lead to a loss of mobility in chronic muscle disorders, such as muscular dystrophy. However, the in vivo properties of adipogenic stem and precursor cells remain unclear, mainly due to the high cell heterogeneity in skeletal muscles. Here, we use single-cell RNA sequencing to decomplexify interstitial cell populations in healthy and dystrophic skeletal muscles. We identify an interstitial CD142-positive cell population in mice and humans that is responsible for the inhibition of adipogenesis through GDF10 secretion. Furthermore, we show that the interstitial cell composition is completely altered in muscular dystrophy, with a near absence of CD142-positive cells. The identification of these adipo-regulatory cells in the skeletal muscle aids our understanding of the aberrant fat deposition in muscular dystrophy, paving the way for treatments that could counteract degeneration in patients with muscular dystrophy.